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101.
纳米锐钛矿型TiO_2的溶胶-凝胶法制备及其表征   总被引:1,自引:0,他引:1  
以钛白粉厂价格低廉的偏钛酸为原料,采用溶胶 凝胶法,结合微乳化技术和共沸蒸馏的工艺路线,制备了纳米锐钛矿型TiO2粉体。用电镜(TEM)及X射线衍射(XRD)技术进行了表征。结果表明:TiO2结晶良好,分布均匀,无团聚现象。粒径为30~50nm。TiO2粉体为锐钛矿结构,质量分数达99%。  相似文献   
102.
反相微乳液聚合机理及模型化处理   总被引:7,自引:0,他引:7  
在阐述反相微乳液聚合液滴成核及粒子增长机理的基础上,提出了丙烯酰胺反相微乳液聚合过程的物理模式,并对反相微乳液聚合模型化处理时的关键问题作了扼要讨论。  相似文献   
103.
AM/SA反相微乳液聚合反应动力学研究   总被引:2,自引:0,他引:2  
以油酸失水山梨醇酯Span80和壬基酚聚氧乙烯醚OP-10为乳化剂,白油为连续介质,高活性过氧化二碳酸(2-乙基已基)酯(EHP)为引发剂,进行了丙烯酰胺/丙烯酸钠(AM/SA)反相微乳液共聚合反应。研究了单体总浓度[M],引发剂浓度[I],乳化剂浓度[E]对AM/SA反相微乳液聚合速率Rp和共聚物分子量M^-v的影响规律,得到Rp∞[M]^m[I]^0.65[E]^0.34,M^-v∞[M]^n[I]^-0.30[E]^-1.08,其中当[M]=3.21mol/L-6.42mol/L时,m=2.34,n=0.68,当[M]=1.28mol/L-3.33mol/L时,m=1.61,n=0.58,比较了不同单体浓度范围内AM/SA反相微乳液聚合速率。  相似文献   
104.
Study on catalytic combustive reaction of dimethyl ether as a new fuel was presented. Hexaaluminate catalysts were used to reduce ignition temperature so that dimethyl ether completely combusted at low temperature. Hexaaluminate catalysts MnLaAl11O19-δ were prepared by reverse microemulsion method. Crystalline phase and structure of the catalyst were analysed by means of TG-DTA, XRD and BET. The results show that the hexaalunminate is of magnetoplumbite structure when La is taken as mirror plane cation. Hexaalunminate phase is formed slowly via 1050 ℃ calcined for 4 h and it can keep hexaaluminate phase and high surface area of 48 m2·g-1 even calcined at 1200 ℃ for 2h. Catalytic activity of MnLaAl11O19-δ was tested in combustion reaction of dimethyl ether. It shows that hexaaluminate is of high activity with T 10% at 170 ℃ and almost 100% conversion at 370 ℃.  相似文献   
105.
The formation of water-in-oil (W/O) microemulsion with a water phase and diesel oil as the oil phase, with the cationic surfactant oleinic acid and linoleinic acid and alcoholic cosurfactant, has been examined. The various factors that influence the amount of water added are studied. The experimental result shows that the quantity of ammonia and alcohol, the alcoholic cosurfactant chain length, and the concentration of the inorganic salt have substantial effects on the formation of the microemulsion and the amount of water added. The neutralization value of ammonia to oleinic acid has an optimum value at which the amount of solubilization water is the largest. The alcohols that have moderate carbon chain length can achieve a larger amount of solubilization water, among which n-butanol has the best effect. The addition of a certain amount of inorganic salt can increase the amount of water added. The mixed surfactant is superior to the single surfactant and there exists an optimum proportion. The amount of surfactant added could be decreased considerably by mixing the cationic surfactant and anionic surfactant together in a certain proportion. The action of ammonia, alcohol, and inorganic salt in the formation of the microemulsion is explained theoretically. The mechanism of interaction between the cationic surfactant and anionic surfactant is depicted in detail. The condensed diesel microemulsion was made and the method of the industrial application is discussed.  相似文献   
106.
The mixing and mass transfer characteristics of draft‐tube airlift bioreactors (DTAB) for a water‐in‐kerosene microemulsion, as a cold model of petroleum biodesulfurization, were studied. Incomplete gas disengagement at the top‐section of the DTAB and hence high gas recirculation were obtained with the microemulsion system for all the top‐section configurations employed in the present study especially at the high airflow rates. The ratio (S) of the volumes of the riser and the downcomer to the top‐section together with the gas disengagement abilities of the gas separator were both found to affect the mixing performance of the DTAB employed for the microemulsion system. Increase in the draft‐tube height resulted in significant increase in the mixing time (tm) and a slight increase in the overall volumetric oxygen transfer coefficient (kLa). Increase in the diameter of the top‐section and the height of the liquid above the draft‐tube led to a decrease in kLa, the latter effect being less prominent. New correlations were developed that predicted the mixing time and oxygen transfer coefficients obtained in the present work with reasonable accuracy. Copyright © 2004 Society of Chemical Industry  相似文献   
107.
以丙烯酰胺、丙烯酰氧基乙基三甲基氯化铵、聚氧乙烯大单体和N ,N’ -亚甲基双丙烯酰胺为单体 ,进行四元反相微乳液共聚合 ,制备出新型含PEO支链的阳离子微粒絮凝剂。然后用该微粒絮凝剂分别对针叶木纸浆和特种纸白水进行了助留和絮凝性能的研究 ,结果表明 ,本新型微粒具有能单独使用、絮凝效果好和抗剪切性强等优点。  相似文献   
108.
测算了由二(2-乙基己基)磷酸钠,金属盐(CoSO4,NiSO4,ZnSO4,MgCl2或Cr(NO3)3)水溶液,正辛醇和正辛烷组成的微乳液中正辛醇从连续油相到界面的ΔGo→i^o和水的极限增容量φ'H2O。用金属萃取络合物反胶束的形成及其亲油性解释了金属离子对φ'H2O和ΔGo→i^o的影响。  相似文献   
109.
对水热法制备的LaMnAl11O19-α(LMA)催化剂和微乳液法制备的Ce0.5Ba0.5MnAl11O19-α(CBMA)催化剂进行了100h的甲烷催化燃烧活性试验,考察了反应条件下的水蒸气处理对催化剂的结构和甲烷催化燃烧活性的影响。结果表明:反应条件下的水蒸气处理促进了水热法制备的LMA催化剂中的六铝酸盐相晶粒长大,比表面积降低,从而引起活性下降。对微乳液法制备的CBMA催化剂,反应条件下的水蒸气处理使得催化剂中的γ-Al2O3转化为α-Al2O3从而引起比表面积的大幅度降低,但催化活性没有出现明显变化,仍保持着较高的甲烷燃烧活性。  相似文献   
110.
本文采用反相微乳液聚合的方法合成了丙烯酰胺(AM)/丙烯酰氧基乙基三甲基氯化铵(AD-AMQUAT)/聚氧乙烯大单体(PEO-A)/N,N'-亚甲基双丙烯酰胺(Bis)的四元共聚物微粒.研究了该微粒助留剂的结构与性能.这种微粒和纸纤维能够通过离子键和氢键作用显著地增强助留效果.  相似文献   
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